System and method for recursive propagating application access control

ABSTRACT

A method includes receiving, at a cloud storage system, a request to access a file from an external application on behalf of a first user account, determining, based on one or more access control lists (ACLs) associated with a shared folder, that the external application is not allowed to access the file on behalf of the first user account, and receiving, from a user device associated with the first user account, a message authorizing the external application to access the file on behalf of the first user account. The method further includes modifying the ACLs associated with the shared folder containing the file and a subfolder, and allowing the external application to access the file on behalf of the first user account based on the user information of the first user account and the application information of the external application in the modified ACLs.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation application of co-pending U.S. patentapplication Ser. No. 16/398,198, filed Apr. 29, 2019, which is acontinuation of U.S. patent application Ser. No. 14/709,179, filed May11, 2015, now U.S. Pat. No. 10,277,601, each of which is incorporatedherein by reference.

BACKGROUND

A cloud storage user can install and use third-party applications. Someapplications benefit from accessing content created outside of theapplication. For example, a photo editor application may not createcontent, but the photo editor application can access some existing imagecontent to enhance, crop, and perform other modifications to thecontent. However, a user may not trust a third-party application toaccess all of their content. For example, a user can configure differentaccess permission to folders or contents such that third-partyapplications may not have access to private and confidential content,but the third-party application may be able to access public content,e.g., a user can allow a third-party drive application to edit thephotos in a public folder on the user's cloud storage.

To open all the photos with the third-party application, when the userhas all images in a single directory named “Photos,” the user usuallybrowses and opens all the images from within the image viewingapplication by first performing an “open” operation in the cloud storageUser Interface (UI) on each and every image to make the image accessibleto the application. Similarly, when the user puts media files in analbum folder, the user cannot open the album folder in a music playerapplication and play all the songs in it, or a zip 20 creatorapplication cannot zip up the contents of a folder unless the userexplicitly opens each and every file beforehand.

Existing mechanisms to manage sharable storage for limiting third-partyapplication access to user content do not allow a user to configurespecific access control to folders or contents. In that case, users maygrant overly-broad access to applications or have to grant access toeach file one-by-one in a tedious manner. For example, applications maybe granted access to read all files of a particular type, which may betoo narrow or too broad access. In another example, to configure accesscontrol for a particular application, the content usually has to bestored in a location private to the application, making it inaccessibleto other applications. For example, some wire framing applications maystore multiple types of files in a project organized in specific folderssuch that other applications cannot access. Some of the files are commonfile types (such as images) which other applications may be able tosupport. The user can grant the wire framing application access only tocertain project folders, and prevent another application from havingaccess to the content the images wire framing application uses becausethey would reside in a folder private to the particular wire framingapplication. In another example, some file transfer and storageapplications may allow third-party applications to access a singlefolder owned by the application itself, or to have access to all filesof a specific type on the cloud drive. Such access configuration,however, grants all-or-nothing access authorization to a certain folderor a certain file type on a user's storage drive associated with therespective file transfer and storage application itself, but does notallow restricting certain file types of a particular folder. For anotherexample, some file storage applications only allow access to all of auser's content or all of an enterprise's content stored on an onlinedrive associated with the file storage application, without specificconfiguration to grant an application access to a subset of specificcontent on the user's content on the online drive.

SUMMARY

A system and method for recursive propagating application access controlis described which relates to managing third-party application access tocontent files and folders on a cloud storage system. The access controlsystem may receive an access authorization indication to grant athird-party entity access to a first file in a parent folder, and thenmodify an access control rule associated with the parent folder based onthe access authorization indication. The modified access control rule ispropagated to a child folder of the parent folder, and thus thethird-party entity is granted access to a second file in the childfolder 20 based on the modified access control rule. The second fileshares a common attribute with the first file, and the modified accesscontrol rule specifies the common attribute.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a schematic diagram of a system for application-specificaccess control in accordance with one or more implementations of thedisclosure.

FIG. 2 is an example block diagram illustrating aspects of top-down ACLpropagation among a hierarchy of folders and files, according to someimplementations of the disclosure.

FIG. 3 is an example block diagram illustrating aspects of user-specificaccess propagation, according to some implementations of the disclosure.

FIG. 4 is an example logic flow diagram illustrating aspects ofapplication access propagation for third-party access control, accordingto some implementations of the disclosure.

FIGS. 5-6 are example logic flow diagrams illustrating aspects offallback search for third-party application access, according to someimplementations of the disclosure.

FIGS. 7-9 are example user interface (UI) diagrams illustratingthird-party application access control on a cloud storage system,according to some implementations of the disclosure.

FIG. 10 is a schematic diagram of an exemplary computer system employedin accordance with one or more implementations of the disclosure.

Implementations are described with reference to the accompanyingdrawings. In the drawings, like reference numbers may indicate identicalor functionally similar elements. The drawing in which an element firstappears is generally indicated by the left-most digit in thecorresponding reference number.

DETAILED DESCRIPTION

To provide an overall understanding of the systems and methods describedherein, certain illustrative implementations will now be described.However, it will be understood by one of ordinary skill in the art thatthe systems and methods described herein may be adapted and modified asis appropriate for the application being addressed and that the systemsand methods described herein may be employed in other suitableapplications, and that such other additions and modifications will notdepart from the scope thereof. Generally, the computerized systemsdescribed herein may comprise one or more engines, which include aprocessing device or devices, such as a computer, microprocessor, logicdevice or other device or processor that is configured with hardware,firmware, and software to carry out one or more of the computerizedmethods described herein.

The present disclosure provides systems and methods for providingthird-party applications with access to file content on a web-basedstorage system. Specifically, a user can configure user-specific andapplication-specific access control for a third-party application toaccess file content. For example, a user can authorize a third-partyapplication to access a file or a folder on the cloud storage, e.g., byopening a file within the third-party application, by editing orcreating a file within the third-party application, etc., and the accessauthorization can be propagated downwardly to subfolders of the foldersuch that the third-party application is automatically granted access tosubfolders of the folder, without the user having to further specify theaccess authorization in the subfolders. The systems and methodsdisclosed herein are described in terms of third-party applications orapplications. In general, the systems and methods are applicable tothird-party entities, such as third-party users, third-party operatingsystems, third-party servers, and/or the like. The systems and methodsdisclosed herein are described in terms of a web-based storage system,which may communicate with other systems over a network to store andshare user data. In general, one of ordinary skill in the art willunderstand that the systems and methods described herein are applicableto systems that are locally interconnected without departing from thescope thereof.

FIG. 1 depicts an example of a network and database structure that maybe used to implement the systems and methods herein. FIG. 1 is a blockdiagram of a computerized system 100 for allowing third-partyapplications to access representations of files stored on a web-basedstorage system. The system 100 includes a web-based storage system 101,a user device 114, and a third-party system 103. The web-based storagesystem 101 includes a server 104 including a processor 105, a contentdatabase 106, an access control module 113 and a metadata database 109.The access control module 113 may be integrated with the processor 105and the server 104, and/or may be a standalone component, hardware orsoftware module. The third-party system 103 includes a third-partydatabase 107, a third-party server 108 including a processor 110, and adeveloper device 112. As used herein, the term “processor” or “computingdevice” refers to one or more computers, microprocessors, logic devices,servers, or other devices configured with hardware, firmware, andsoftware to carry out one or more of the computerized techniquesdescribed herein. Processors and processing devices may also include oneor more memory devices for storing inputs, outputs, and data that arecurrently being processed. An illustrative computing device 1000, whichmay be used to implement any of the processors and servers describedherein, is described in detail with reference to FIG. 10 . As usedherein, “developer device” and “user device” include, withoutlimitation, any suitable combination of one or more input devices (e.g.,keypads, touch screens, trackballs, voice recognition systems, etc.)and/or one or more output devices (e.g., visual displays, speakers,tactile displays, printing devices, etc.). As used herein, “server”includes, without limitation, any suitable combination of one or moredevices configured with hardware, firmware, and software to carry outone or more of the computerized techniques described herein. Only oneweb-based storage system 101, one user device 114, and one third-partysystem 103 are shown in FIG. 1 to avoid complicating the drawing. Ingeneral, the system 100 can support multiple web-based storage systems,third-party systems, servers, databases, developer devices, and userdevices.

The web-based storage system 101 is a file hosting system that allowsusers to store, retrieve, and modify data via one or more user devicessuch as the user device 114. This data may be referred to as a user'sweb data. As an example, the web-based storage system 101 may be storedon a single server system or in a distributed system. In particular, theweb-based storage system 101 may use cloud storage to store user data.

The content database 106 stores content files, which may be viewed oredited using various applications such as native applications, orthird-party applications. Native applications correspond to internal,first-party applications in the web-based storage system 101. As anexample, the native application may provide access between the user andthe native file over a web browser (i.e., for viewing and/or editing anative document). Alternatively, files in the content database 106 maybe accessed, edited, and/or saved via a third-party application, e.g.,applications that are not internal to or affiliated with the web-basedstorage system 101. For example, a photo management application caninclude a third-party application that is different from a user or acloud storage system, which can access stored images at the cloudstorage system on behalf of the user, to facilitate the user to view,edit, create, delete or perform other operations with the stored images.

The metadata database 109 stores several types of data. In particular,the metadata database 109 stores metadata associated with file contentstored on the web-based storage system 101 or on the third-party system103. The metadata may include file ownership information, editinghistory, authorship information, blacklist or whitelist accessinformation, file type, and/or the like. For example, the metadata mayinclude an application access list (ACL) entry that specifiesthird-party applications that are authorized to access a file or afolder. Such access control information can also be referenced in thethird-party database 107, e.g., for data entries associated with athird-party application.

The third-party system 103 communicates with the web-based storagesystem 101 over the network 102 to access a representation of a nativefile stored on the native database 106. As depicted in FIG. 1 , thethird-party system 103 includes a third-party database 107, athird-party server 108, and a developer device 112. The third-partydatabase 107 may store third-party files in a particular format suitablefor the third-party system 103.

It is sometimes desirable for the third-party application to access thecontents of a content file so that the third-party application canoperate on file content. The third-party application may be unable todirectly access the raw content of the file if the ACL entry associatedwith the file does not include the third-party application. The accesscontrol module 113 (via the processor 105) may grant access to athird-party application to access content files in the content database106. The third-party application may then use one or more applicationprogramming interfaces (APIs) to access files on the web-based storagesystem 101.

To provide access of the content of the native file to the third-partyapplication, the processor 105 and/or the access control module 113 maycreate or modify an ACL entry associated with a folder or a file, andthen propagate the modification of the ACL entry downwardly to ahierarchy of subfolders of the instant folder such that the third-partyapplication may be able to access content files in the subfolderswithout further explicit user authorization. In some instances, the ACLentry can be user specific, e.g., a third-party application isauthorized access to contents on behalf of a user but may be deniedaccess to the same contents when acting on behalf of anotherunauthorized user. In a further implementation, the ACL entry can becontent or file-type specific, e.g., access for the third-partyapplication may be restricted to a certain file or content type, and/orthe like.

FIG. 2 is an example block diagram illustrating aspects of top-down ACLpropagation among a hierarchy of folders and files, according to someimplementations of the disclosure. In some instances, a third-partyapplication (e.g., “my photo manager” 220) is granted access to a folderand/or a file 205 at an access event 221, including but not limited tothe following scenarios: the third-party application has been used toopen and view files, save changes to files that are opened using thethird-party application, or create new files using the third-partyapplication, at a cloud storage system.

When the access event 221 is captured at the level of the instantfolder, e.g., “my folder” 205, the ACL entry associated with the foldercan be modified to allow access for the third-party application, and themodification can be propagated (e.g., ACL propagation 200) to the subfolders (e.g., subfolder 208, subfolder 212, etc.) of “my folder” 205.Upon the ACL propagation, contents of “my folder” 205, contents of“subfolder” 208, and contents of “subfolder” 212 may be accessible bythe third-party application “my photo manager” 200. In a furtherimplementation, the ACL propagation may be content-specific. In therespective example shown in FIG. 2 , the third-party application “myphoto manager” 220 may be granted access to image content, e.g., forfiles with an image file format such as but not limited to JPG, BMP,PNG, GIF, and/or the like. Thus the third-party application “my photomanager” 220 may access “File1.jpg” 206 in the “my folder” 205, and“file3.bmp” 211 in the subfolder 208, but not “file2.ppt” 207, which isnot of an authorized content type although it is within theaccess-allowed folder.

FIG. 3 is an example block diagram illustrating aspects of user-specificaccess propagation, according to some implementations of the disclosure.In some instances, the access propagation can be user-specific, e.g., athird-party application may only access contents and folders on thecloud storage on behalf of a particular user, if the particular usergrants the third-party application access in the first place. As shownin FIG. 3 , a first user (e.g., “Jack” 302 a) can instantiate athird-party application 320 a, to access a file such as a photo 305under a share folder 303 on the cloud storage (e.g., at 311). Forexample, user “Jack” 302 a may login to the photo manager application toengage the photo manager to open and/or edit a photo 305. In this way,the ACL entry associated with the share folder 303 may be modified withinformation specific to user “Jack” 302 a, and the ACL propagation 312can be propagated to subfolder 306 with user specific information. Thus,user “Jack” 302 a can operate the photo manager 320 a (e.g., by logininto his account) and access to a photo 307 under the sub folder 306(e.g., at 313). Another user “Rose” 302 b, may not be able to access thephoto 307 with the same third-party application 320 b but logged in withRose's information, e.g., at 314, because the ACL propagation has onlyauthorized access on behalf of user “Jack.” In this way, when user“Jack” 302 a has used a third-party application to access his privatecontent, a different user (e.g., user “Rose” 302 b) may not be able toengage the same third-party application to access such content.

FIG. 4 is an example logic flow diagram 400 illustrating aspects ofapplication access propagation for third-party application accesscontrol, according to some implementations of the disclosure. In someinstances, an access control module (e.g., 113 in FIG. 1 ) at a cloudstorage system may receive an access authorization indication for athird-party application to access a file or a folder, e.g., at 402. Forexample, the access authorization indication may include but not belimited to a user opening a folder or a file using the third-partyapplication, viewing a folder or a file using the third-partyapplication, creating a new folder or a file using the third-partyapplication, saving changes to a file using the third-party application,and/or the like. The access control module may then determine a folderand/or a subfolder the file is located at, e.g., at 404. For example,the folder where the file is located can be a parent folder of anotherchild folder, and/or can be a child folder of another parent folder.

In some instances, the access control module can optionally verify thatthe user has the right to grant access to the folder or file for thethird-party application, e.g., at 406. For example, when a user attemptsto engage a third-party application to access private content that hasbeen configured with limited access by another user, access may bedenied, and the user may not be able to access or grant access to thefolder or file for the third-party application.

At 408, the access control module may modify an ACL entry of the folderto include the third-party application information, user information,and (optional) file/content type information, and/or the like. Forexample, the cloud storage may employ an API scope to optionallypropagate ACL updates and add a per-item and per-user AppAcl field tothe ACL entry. At 410, the modification can be propagated to subfolders,e.g., children folders of the folder. For example, the access controlmodule can propagate the AppAcl field from parent to children with atask and add AppAcl entries to the authorized applications CSV. A“propagate” flag can be added to a data field that shows the status ofpropagation. For example, when the status is true, the mode ofpropagation is set to ACTIVE (propagating) on the ACL entry; when false,the mode can be set to LEGACY (non-propagating) on the ACL entry.

In some instances, changes in an ACL entry can propagate to childrenwhen a parent is added, e.g., a file can be placed in a folder, orreside in multiple folders. An ACL entry can be revoked by its owner,but removal of application ACL entries may not propagate; instead, auser-initiated revoke-all operation can remove entries, such asuninstallation of the application, deleting (and then restoring) afolder or a file. For example, a separate application version schemeallows files or folders which are not in the user's corpus at uninstalltime to be revoked, e.g., when an application is installed, a counterstored in a user attribute data field is incremented; when anapplication ACL entry is added, the current value of this counter isinserted with it; when application ACL entries are returned, those withvalues less than the current counter can be ignored. This scheme allowsthe application ACL cleanup process at uninstall time to be efficientwhile still ensuring immediate revocation. An example pseudo-codesegment illustrating an application ACL propagation operation can take aform similar to the following:

// An application ACL.

message AppAcl {

// The unordered list of authorized applications.

repeated AppAclEntry entry=1

}

// Authorization for a single application.

message AppAclEntry {

// The application to grant access to.

optional AppAclId id=1;

// The time when access was granted in milliseconds since the epoch.

optional int64 grant time millis=2;

// The behavior modes a file scope app ACL entry can possess.

enum FileScopeMode {

// Original file scope behavior: entry was explicitly opened and should

// not propagate.

LEGACY=0;

// Access was propagated to this entry, it was not explicitly opened.

PASSIVE=1;

// Entry was explicitly opened and propagates access to children.

ACTIVE=2;

}

// Must be set if and only if id.type is FILE_SCOPE.

optional FileScopeMode file_scope_mode=4;

}

// The unique identifier of an application ACL entry.

message AppAclId {

enum IdType {

FILE_SCOPE=1;

}

// The type of app ACL entry.

Optional IdType type=1;

// The app ID. See http://go/devconsole-projectid for app ID spec.

optional string app_id=2;

// The Gaia ID of the user this app ACL entry applies to.

optional int64 user_gaia_id=3;

}

// This message is added as a new field to the DirEntry message:

message DirEntry {

. . .

optional AppAcl app_ad=1234;

. . . }

In some instances, the downward propagation may happen when an accessauthorization indication takes place at a folder (e.g., when thethird-party application has been authorized to access a folder), thenthe ACL propagates to all the files and subfolders within the folderrecursively, e.g., at each subfolder level, the propagation is repeateddownwardly through the hierarchy of folders. In some instance, if theaccess authorization is performed at a specific file, the accessauthorization may not propagate to subfolders in the current folderwhere the specific file is located. In further instances, propagationcan terminate at an inaccessible item, e.g., when a subfolder of anauthorized folder is configured to be “private,” the propagation may notextend to the private folder.

FIGS. 5-6 are example logic flow diagrams 500-600 illustrating aspectsof fallback search for third-party application access, according to someimplementations of the disclosure. The propagation that implementsfolder access inheritance can be done asynchronously, becausesynchronous propagation may be prohibitively expensive. For example, thedownward ACL propagation may not occur immediately when a third-partyapplication is granted access to a parent folder, and the applicationmay not be able to access all content within the folder immediately. Toaddress this issue, a fallback search can be performed up the parenttree for application access o allow an application to access all contentas soon as the folder is granted access, which may achieve a comparablesynchronization performance as synchronous propagation.

As shown in FIG. 5 , a cloud storage system can receive an accessrequest from a third-party application to access a file located within afolder or subfolder, e.g., at 502. An access control module may identifyuser information and third-party application information from therequest at 504. If an ACL entry associated with the current folderexists and authorizes the third-party application to access at 506, therequest may be granted at 508. Otherwise, a fallback search can beimplemented by identifying a folder hierarchy at 512 and searching upthe parent folder for an ACL entry at 514.

Continuing on with FIG. 6 , if an ACL entry exists at the parent folderto authorize access for the third-party application at 602, thethird-party application may be granted access to access the file at 604,and the ACL entry can be propagated to the child folder/subfolder wherethe file is located, e.g., at 606. Otherwise, if the first-degree parentfolder does not have such ACL entries and if there is another level ofparent folder at 608, the fallback search may optionally move up to asecond-degree parent folder at 612. If there is no other second-degreeparent folder, then the access request may be denied at 610. Thefallback search on the entire parent tree may also be prohibitivelyexpensive. Additional fallback search rules may apply to restrict thesearch to ID queries, limited degrees of parent folder search, listedchild folder search, and/or the like.

FIGS. 7-9 are example user interface (UI) diagrams illustratingthird-party application access control on a cloud storage system,according to some implementations of the disclosure. As shown in FIG. 7, a user can access a cloud storage system via a web browser UI 700. Theuser can grant access for a third-party application to access a folder702 by right-clicking to obtain an “Open with” context menu at 704. Theuser can then select to “Open With” a third-party application such as“Music Player” 706, the Music Player application 706 can then gainaccess to the folder 704 and all of its children.

As shown in FIG. 8 , the third-party application, e.g., “Music Player”can provide a file picker widget UI 800 to prompt a user to select filesthat the application does not currently have access to. Upon userselection, the application can gain access to the selected item(s),e.g., folder 802, and the children of folders are also authorized whenthe folder 802 is selected.

As shown in FIG. 9 , the cloud storage system may prompt a user toconfirm authorization with an initial authorization dialog box 900,e.g., to confirm that the user agrees to view and manage cloud filesand/or folders that are opened or created within the application at 902.For example, upon confirmation of access authorization, a user may viewfiles from the cloud storage that have been opened with this applicationor that are shared publicly; save changes to files that are opened withthis app; create new files in the cloud storage using this app; viewfolders and their contents from the cloud storage that are opened withthis app; make changes to folders and their contents that are openedwith this app; delete contents of folders that are opened with thisapplication, and/or the like.

In further implementations, the access control operations discussed inconnection with FIGS. 1-9 can be employed in various different ways. Forexample, the access control module may adopt synchronous propagationwhen an authorization indication is received. Or alternatively, fallbacksearch tree for a folder can be implemented for granting access at alltimes without ACL propagation. Shared application access can be granted,e.g., if user A grants an application access to a shared folder, thenthe application can read that folder as user B. Instant accessrevocation for an entire application can be performed without having touninstall the application.

The approaches and systems described herein may be deployed in part orin whole through a machine that executes computer software, programcodes, and/or instructions on one or more processors contained in theclient devices and/or the server or servers associated with theweb-based storage system.

Implementations of the disclosure may include a method on a machine, asystem or apparatus as part of or in relation to the machine, or acomputer program product embodied in a computer readable mediumexecuting on one or more of the machines. The one or more processors maybe part of a server, client, network infrastructure, mobile computingplatform, stationary computing platform, or other computing platform.

A processor may be any kind of computational or processing devicecapable of executing program instructions, codes, binary instructionsand the like. The processor may include memory that stores methods,codes, instructions and programs as described herein and elsewhere. Theprocessor may access a storage medium through an interface that maystore methods, codes, and instructions as described herein andelsewhere. The storage medium associated with the processor for storingmethods, programs, codes, program instructions or other type ofinstructions capable of being executed by the computing or processingdevice may include but may not be limited to one or more of a CD-ROM,DVD, memory, hard disk, flash drive, RAM, ROM, cache and the like.

FIG. 10 is a block diagram illustrating an exemplary computer system1000 with which the system for access control propagation and use ofFIGS. 1-9 can be implemented. In certain aspects, the computer system1000 may be implemented using hardware or a combination of software andhardware, either in a dedicated server, or integrated into anotherentity, or distributed across multiple entities.

Computer system 1000 includes a bus 1008 or other communicationmechanism for communicating information, and a processor 1002 coupledwith bus 1008 for processing information. By way of example, thecomputer system 1000 may be implemented with one or more processors1002.

Computer system 1000 can include, in addition to hardware, code thatcreates an execution environment for the computer program in question,e.g., code that constitutes processor firmware, a protocol stack, adatabase management system, an operating system, or a combination of oneor more of them stored in an included memory 1004, such as a RandomAccess Memory (RAM), a flash memory, a Read Only Memory (ROM), aProgrammable Read-Only Memory (PROM), an Erasable PROM (EPROM),registers, a hard disk, a removable disk, a CD-ROM, a DVD, or any othersuitable storage device, coupled to bus 1008 for storing information andinstructions to be executed by processor 1002. The processor 1002 andthe memory 1004 can be supplemented by, or incorporated in, logiccircuitry.

The methods and systems described herein may be deployed in part or inwhole through a machine that executes computer software on a server,client, firewall, gateway, hub, router, or other such computer and/ornetworking hardware. The software program may be associated with aserver that may include a file server, print server, domain server,internet server, intranet server and other variants such as secondaryserver, host server, distributed server and the like. The server mayinclude one or more of memories, processors, computer readable media,storage media, ports (physical and virtual), communication devices, andinterfaces capable of accessing other servers, clients, machines, anddevices through a wired or a wireless medium, and the like. The methods,programs or codes as described herein and elsewhere may be executed bythe server. In addition, other devices required for execution of methodsas described in this application may be considered as a part of theinfrastructure associated with the server.

The server may provide an interface to other devices including, withoutlimitation, clients, other servers, printers, database servers, printservers, file servers, communication servers, distributed servers andthe like. Additionally, this coupling and/or connection may facilitateremote execution of programs across the network. The networking of someor all of these devices may facilitate parallel processing of a programor method at one or more location without deviating from the scope ofthe disclosed subject matter. In addition, any of the devices attachedto the server through an interface may include at least one storagemedium capable of storing methods, programs, code and/or instructions. Acentral repository may provide program instructions to be executed ondifferent devices. In this implementation, the remote repository may actas a storage medium for program code, instructions, and programs.

The methods and systems described herein may be deployed in part or inwhole through network infrastructures. The network infrastructure mayinclude elements such as computing devices, servers, routers, hubs,firewalls, clients, personal computers, communication devices, routingdevices and other active and passive devices, modules and/or componentsas known in the art. The computing and/or non-computing device(s)associated with the network infrastructure may include, apart from othercomponents, a storage medium such as flash memory, buffer, stack, RAM,ROM and the like. The processes, methods, program codes, instructionsdescribed herein and elsewhere may be executed by one or more of thenetwork infrastructural elements.

The computer software, program codes, and/or instructions may be storedand/or accessed on machine readable media that may include: computercomponents, devices, and recording media that retain digital data usedfor computing for some interval of time; semiconductor storage known asrandom access memory (RAM); mass storage typically for more permanentstorage, such as optical discs, forms of magnetic storage like harddisks, tapes, drums, cards and other types; processor registers, cachememory, volatile memory, non-volatile memory; optical storage such asCD, DVD; removable media such as flash memory (e.g. USB sticks or keys),floppy disks, magnetic tape, paper tape, punch cards, standalone RAMdisks, Zip drives, removable mass storage, off-line, and the like; othercomputer memory such as dynamic memory, static memory, read/writestorage, mutable storage, read only, random access, sequential access,location addressable, file addressable, content addressable, networkattached storage, storage area network, bar codes, magnetic ink, and thelike.

The elements described and depicted herein, including in flow charts andblock diagrams throughout the figures, imply logical boundaries betweenthe elements. However, according to software or hardware engineeringpractices, the depicted elements and the functions thereof may beimplemented on machines through computer executable media having aprocessor capable of executing program instructions stored thereon as amonolithic software structure, as standalone software modules, or asmodules that employ external routines, code, services, and so forth, orany combination of these, and all such implementations may be within thescope of the present disclosure.

Thus, while the foregoing drawings and descriptions set forth functionalaspects of the disclosed systems, no particular arrangement of softwarefor implementing these functional aspects should be inferred from thesedescriptions unless explicitly stated or otherwise clear from thecontext. Similarly, it will be appreciated that the various techniquesidentified and described above may be varied, and that the order oftechniques may be adapted to particular applications of the techniquesdisclosed herein. All such variations and modifications are intended tofall within the scope of this disclosure. As such, the depiction and/ordescription of an order for various techniques should not be understoodto require a particular order of execution for those techniques, unlessrequired by a particular application, or explicitly stated or otherwiseclear from the context.

The methods and/or processes described above, and techniques thereof,may be realized in hardware, or any combination of hardware and softwaresuitable for a particular application. The hardware may include ageneral purpose computer and/or dedicated computing device or specificcomputing device or particular aspect or component of a specificcomputing device. The processes may be realized in one or moremicroprocessors, microcontrollers, embedded microcontrollers,programmable digital signal processors or other programmable device,along with internal and/or external memory. The processes may also, orinstead, be embodied in an application-specific integrated circuit, aprogrammable gate array, programmable array logic, or any other deviceor combination of devices that may be configured to process electronicsignals. It will further be appreciated that one or more of theprocesses may be realized as a computer executable code capable of beingexecuted on a machine readable medium.

The instructions may be stored in the memory 1004 and implemented in oneor more computer program products, i.e., one or more modules of computerprogram instructions encoded on a computer readable medium for executionby, or to control the operation of, the service, and according to anymethod well known to those of skill in the art, including, but notlimited to, computer languages such as data-oriented languages (e.g.,SQL, dBase), system languages (e.g., C, Objective-C, C++, Assembly),architectural languages (e.g., Java .NET), and application languages(e.g., PHP, Ruby, Perl, Python).

A computer program as discussed herein does not necessarily correspondto a file in a file system. A program can be stored in a portion of afile that holds other programs or data (e.g., one or more scripts storedin a markup language document), in a single file dedicated to theprogram in question, or in multiple coordinated files (e.g., files thatstore one or more modules, subprograms, or portions of code). A computerprogram can be deployed to be executed on one computer or on multiplecomputers that are located at one site or distributed across multiplesites and interconnected by a communication network. The processes andlogic flows described in this specification can be performed by one ormore programmable processors executing one or more computer programs toperform functions by operating on input data and generating output.

Computer system 1000 further includes a data storage device 1006 such asa magnetic disk or optical disk, coupled to bus 1008 for storinginformation and instructions. Computer system 1000 may be coupled via aninput/output module 1010 to various devices. The input/output module1010 can be any input/output module. Example input/output modules 1010include data ports such as USB ports. The input/output module 1010 isconfigured to connect to a communications module 1012. Examplecommunications modules 1012 include networking interface cards, such asEthernet cards and modems. In certain aspects, the input/output module1010 is configured to connect to a plurality of devices, such as aninput device 1014 and/or an output device 1016. Example input devices1014 include a keyboard and a pointing device, e.g., a mouse or atrackball, by which a user can provide input to the computer system1000. Other kinds of input devices 1014 can be used to provide forinteraction with a user as well, such as a tactile input device, visualinput device, audio input device, or brain-computer interface device.For example, feedback provided to the user can be any form of sensoryfeedback, e.g., visual feedback, auditory feedback, or tactile feedback;and input from the user can be received in any form, including acoustic,speech, tactile, or brain wave input. Example output devices 1016include display devices, such as a CRT (cathode ray tube) or LCD (liquidcrystal display) monitor, for displaying information to the user.

According to one aspect of the present disclosure, the system forapplication-specific file type generation and use as shown in FIGS. 1-2, can be implemented using a computer system 1000 in response toprocessor 1002 executing one or more sequences of one or moreinstructions contained in memory 1004. Such instructions may be readinto memory 1004 from another machine-readable medium, such as datastorage device 1006. Execution of the sequences of instructionscontained in main memory 1004 causes processor 1002 to perform theprocesses described herein. One or more processors in a multi-processingarrangement may also be employed to execute the sequences ofinstructions contained in memory 1004. In alternative aspects,hard-wired circuitry may be used in place of or in combination withsoftware instructions to implement various aspects of the presentdisclosure. Thus, aspects of the present disclosure are not limited toany specific combination of hardware circuitry and software.

Various aspects of the subject matter described in this specificationcan be implemented in a computing system that includes a back endcomponent, e.g., as a data server, or that includes a middlewarecomponent, e.g., an application server, or that includes a front endcomponent, e.g., a client computer having a graphical user interface ora Web browser through which a user can interact with an implementationof the subject matter described in this specification, or anycombination of one or more such back end, middleware, or front endcomponents. The components of the system can be interconnected by anyform or medium of digital data communication, e.g., a communicationnetwork. The communication network can include, for example, any one ormore of a personal area network (PAN), a local area network (LAN), acampus area network (CAN), a metropolitan area network (MAN), a widearea network (WAN), a broadband network (BBN), the Internet, and thelike. Further, the communication networks can include, but are notlimited to, for example, any one or more of the following networktopologies, including a bus network, a star network, a ring network, amesh network, a star-bus network, tree or hierarchical network, or thelike. The communications modules can be, for example, modems or Ethernetcards.

As discussed above, computing system 1000 can include clients andservers. A client and server are generally remote from each other andtypically interact through a communication network. The relationship ofclient and server arises by virtue of computer programs running on therespective computers and having a client-server relationship to eachother. Computer system 1000 can be, for example, and without limitation,an enterprise server or group of servers, one or more desktop computers,one or more laptop computers, etc. Computer system 1000 can also beembedded in another device, for example, and without limitation, amobile telephone, a personal digital assistant (PDA), a mobile audioplayer, a Global Positioning System (GPS) receiver, a video gameconsole, and/or a television set top box.

The term “machine-readable storage medium” or “computer readable medium”as used herein refers to any medium or media that participates inproviding instructions to processor 1002 for execution. Such a mediummay take many forms, including, but not limited to, non-volatile media,volatile media, and transmission media. Non-volatile media include, forexample, optical or magnetic disks, such as data storage device 1006.Volatile media include dynamic memory, such as memory 1004. Transmissionmedia include coaxial cables, copper wire, and fiber optics, includingthe wires that comprise bus 1008. Common forms of machine-readable mediainclude, for example, floppy disk, a flexible disk, hard disk, magnetictape, any other magnetic medium, a CD-ROM, DVD, any other opticalmedium, punch cards, paper tape, any other physical medium with patternsof holes, a RAM, a PROM, an EPROM, a FLASH EPROM, any other memory chipor cartridge, or any other medium from which a computer can read. Themachine-readable storage medium can be a machine-readable storagedevice, a machine-readable storage substrate, a memory device, acomposition of matter effecting a machine-readable propagated signal, ora combination of one or more of them.

While this specification contains many specifics, these should not beconstrued as limitations on the scope of what may be claimed, but ratheras descriptions of particular implementations of the subject matter.Certain features that are described in this specification in the contextof separate implementations can also be implemented in combination in asingle implementation. Conversely, various features that are describedin the context of a single implementation can also be implemented inmultiple implementations separately or in any suitable subcombination.Moreover, although features may be described above as acting in certaincombinations and even initially claimed as such, one or more featuresfrom a claimed combination can in some cases be excised from thecombination, and the claimed combination may be directed to asubcombination or variation of a subcombination.

While operations are depicted in the drawings in a particular order,this should not be understood as requiring that such operations beperformed in the particular order shown or in sequential order, or thatall illustrated operations be performed, to achieve desirable results.In certain circumstances, multitasking and parallel processing may beadvantageous. Moreover, the separation of various system components inthe aspects described above should not be understood as requiring suchseparation in all aspects, and it should be understood that thedescribed program components and systems can generally be integratedtogether in a single software product or packaged into multiple softwareproducts.

The subject matter of this specification has been described in terms ofparticular aspects, but other aspects can be implemented and are withinthe scope of the following claims. For example, the actions recited inthe claims can be performed in a different order and still achievedesirable results. As one example, the processes depicted in theaccompanying figures do not necessarily require the particular ordershown, or sequential order, to achieve desirable results. In certainimplementations, multitasking and parallel processing may beadvantageous. Other variations are within the scope of the followingclaims.

What is claimed is:
 1. A method comprising: receiving, by a cloudstorage system that stores a plurality of files for a plurality of useraccounts, a request to access a file of the plurality of files from anexternal content handling application on behalf of a first user accountof the plurality of user accounts, wherein the external content handlingapplication is an application provided by an external system that isconnected to the cloud storage system via a network; determining, by thecloud storage system and based on one or more access control lists(ACLs) associated with a shared folder containing the file stored on thecloud storage system, that the external content handling applicationexecuting on a user device associated with the first user account is notallowed to access the file on behalf of the first user account, whereinthe shared folder is accessible to a set of user accounts including thefirst user account and a second user account of the cloud storagesystem, and wherein the one or more ACLs associated with the sharedfolder do not specify access to files in the shared folder for theexternal content handling application; receiving, by the cloud storagesystem and from the user device associated with the first user account,a message authorizing the external content handling application toaccess the file on behalf of the first user account; and responsive tothe receiving of the message authorizing the external content handlingapplication to access the file on behalf of the first user accountassociated with a first user: modifying, by the cloud storage system andwithout any further input of the first user, the one or more ACLsassociated with the shared folder containing the file and a subfolder onthe cloud storage system, wherein modifying the one or more ACLsassociated with the shared folder comprises including user informationof the first user account and application information of the externalcontent handling application in the one or more ACLs, wherein responsiveto the receiving of the message authorizing the external contenthandling application to access the file on behalf of the first useraccount, the one or more ACLs are modified for the shared folder and notfor the subfolder of the shared folder; and allowing, by the cloudstorage system, the external content handling application to access thefile on behalf of the first user account based on the user informationof the first user account and the application information of theexternal content handling application in the modified ACLs associatedwith the shared folder, wherein the modified ACLs associated with theshared folder prevent the external content handling application toaccess the file on behalf of the second user account.
 2. The method ofclaim 1, further comprising: receiving, by the cloud storage system,another request to access the file from the external content handlingapplication on behalf of the second user account; determining whether togrant or deny access to the file for the external content handlingapplication on behalf of the second user account based on one or moreuser information and one or more application information included in themodified ACLs associated with the shared folder, the one or more userinformation including (i) the user information of the first user accountbut not the user information of the second user account and (ii) the oneor more application information including the application information ofthe external content handling application; and responsive to determiningthat the ACLs associated with the shared folder include the applicationinformation of the external content handling application, but not theuser information of the second user account, denying access to the filefor the external content handling application on behalf of the seconduser account.
 3. The method of claim 1, wherein the modifying of the oneor more ACLs associated with the shared folder comprises: determining anACL associated with the file as the one or more ACLs associated with theshared folder; modifying the ACL associated with the file to include theuser information of the first user account and the applicationinformation of the external content handling application for grantingthe external content handling application access to the file on behalfof the first user account; determining another ACL associated with atleast one of another file of the shared folder, the subfolder of theshared folder, or one or more files stored under the subfolder of theshared folder; and modifying the another ACL to correspond to themodified ACL associated with the file.
 4. The method of claim 3, furthercomprising: receiving, by the cloud storage system, a request of theexternal content handling application to access a file of the one ormore files stored under the subfolder of the shared folder on behalf ofthe first user account; determining that the another ACL is associatedwith the file of the one or more files stored under the subfolder of theshared folder; determining whether to grant or deny access to the fileof the one or more files stored under the subfolder of the shared folderby the external content handling application on behalf of the first useraccount based on one or more user information and one or moreapplication information included in the another ACL; and responsive todetermining that the another ACL includes the user information of thefirst user account and the application information of the externalcontent handling application, allowing the external content handlingapplication to access the file of the one or more files stored under thesubfolder of the shared folder on behalf of the first user account. 5.The method of claim 1, wherein the external content handling applicationis executing on the user device to perform one or more operations withrespect to file content, the one or more operations comprising at leastone of presenting the file content, modifying the file content, deletingat least a portion of the file content, adding new content to the filecontent, or playing the file content.
 6. The method of claim 1, whereinthe receiving of the message granting access to the file furthercomprises verifying that the first user account has privilege to grantaccess to the files.
 7. The method of claim 1, wherein each ACL includesan access control list entry.
 8. A system comprising: a memory; and aprocessing device at a cloud storage system that stores a plurality offiles for a plurality of user accounts, communicatively coupled to thememory to: receive, at the cloud storage system, a request to access afile of the plurality of files from an external content handlingapplication on behalf of a first user account of the plurality of useraccounts, wherein the external content handling application is anapplication provided by an external system connected to the cloudstorage system via a network; determine, by the cloud storage system andbased on one or more access control lists (ACLs) associated with ashared folder containing the file stored on the cloud storage system,that the external content handling application executing on a userdevice associated with the first user account is not allowed to accessthe file on behalf of the first user account, wherein the shared folderis accessible to a set of user accounts including the first user accountand a second user account of the cloud storage system, and wherein theone or more ACLs associated with the shared folder do not specify accessto files in the shared folder for the external content handlingapplication; receive, by the cloud storage system and from the userdevice associated with the first user account, a message authorizing theexternal content handling application to access the file on behalf ofthe first user account; and responsive to the receiving of the messageauthorizing the external content handling application to access the fileon behalf of the first user account associated with a first user:modify, by the cloud storage system and without any further input of thefirst user, the one or more ACLs associated with the shared foldercontaining the file and a subfolder on the cloud storage system, whereinmodifying the one or more ACLs associated with the shared foldercomprises including user information of the first user account andapplication information of the external content handling application inthe one or more ACLs, wherein responsive to the receiving of the messageauthorizing the external content handling application to access the fileon behalf of the first user account, the one or more ACLs are modifiedfor the shared folder and not for the subfolder of the shared folder;and allow, by the cloud storage system, the external content handlingapplication to access the file on behalf of the first user account basedon the user information of the first user account and the applicationinformation of the external content handling application in the modifiedACLs associated with the shared folder, wherein the modified ACLsassociated with the shared folder prevent the external content handlingapplication to access the file on behalf of the second user account. 9.The system of claim 8, wherein the processing device is further to:receive another request to access the file from the external contenthandling application on behalf of the second user account; determinewhether to grant or deny access to the file for the external contenthandling application on behalf of the second user account based on oneor more user information and one or more application informationincluded in the modified ACLs associated with the shared folder, the oneor more user information including (i) the user information of the firstuser account but not the user information of the second user account and(ii) the one or more application information including the applicationinformation of the external content handling application; and responsiveto determining that the ACLs associated with the shared folder includethe application information of the external content handlingapplication, but not the user information of the second user account,deny access to the file for the external content handling application onbehalf of the second user account.
 10. The system of claim 8, wherein tomodify the one or more ACLs associated with the shared folder, theprocessing device is to: determine an ACL associated with the file asthe one or more ACLs associated with the shared folder; modify the ACLassociated with the file to include the user information of the firstuser account and the application information of the external contenthandling application for granting the external content handlingapplication access to the file on behalf of the first user account;determine another ACL associated with at least one of another file ofthe shared folder, the subfolder of the shared folder, or one or morefiles stored under the subfolder of the shared folder; and modify theanother ACL to correspond to the modified ACL associated with the file.11. The system of claim 10, wherein the processing device is further to:receive a request of the external content handling application to accessa file of the one or more files stored under the subfolder of the sharedfolder on behalf of the first user account; determine that the anotherACL is associated with the file of the one or more files stored underthe subfolder of the shared folder; determine whether to grant or denyaccess to the file of the one or more files stored under the subfolderof the shared folder by the external content handling application onbehalf of the first user account based on one or more user informationand one or more application information included in the another ACL; andresponsive to determining that the another ACL includes the userinformation of the first user account and the application information ofthe external content handling application, allow the external contenthandling application to access the file of the one or more files storedunder the subfolder of the shared folder on behalf of the first useraccount.
 12. The system of claim 8, wherein the external contenthandling application is executing on the user device to perform one ormore operations with respect to file content, the one or more operationscomprising at least one of presenting the file content, modifying thefile content, deleting at least a portion of the file content, addingnew content to the file content, or playing the file content.
 13. Thesystem of claim 8, wherein to receive the message granting access to thefile, the processing device is further to verify that the first useraccount has privilege to grant access to the files.
 14. The system ofclaim 8, wherein each ACL includes an access control list entry.
 15. Anon-transitory computer-readable storage medium comprising executableinstructions that when executed, by a processing device at a cloudstorage system that stores a plurality of files for a plurality of useraccounts, cause the processing device to: receive, at the cloud storagesystem, a request to access a file of the plurality of files from anexternal content handling application on behalf of a first user accountof the plurality of user accounts, wherein the external content handlingapplication is an application provided by an external system connectedto the cloud storage system via a network; determine, by the cloudstorage system and based on one or more access control lists (ACLs)associated with a shared folder containing the file stored on the cloudstorage system, that the external content handling application executingon a user device associated with the first user account is not allowedto access the file on behalf of the first user account, wherein theshared folder is accessible to a set of user accounts including thefirst user account and a second user account of the cloud storagesystem, and wherein the one or more ACLs associated with the sharedfolder do not specify access to files in the shared folder for theexternal content handling application; receive, by the cloud storagesystem and from the user device associated with the first user account,a message authorizing the external content handling application toaccess the file on behalf of the first user account; and responsive tothe receiving of the message authorizing the external content handlingapplication to access the file on behalf of the first user accountassociated with a first user: modify, by the cloud storage system andwithout any further input of the first user, the one or more ACLsassociated with the shared folder containing the file and a subfolder onthe cloud storage system, wherein modifying the one or more ACLsassociated with the shared folder comprises including user informationof the first user account and application information of the externalcontent handling application in the one or more ACLs, wherein responsiveto the receiving of the message authorizing the external contenthandling application to access the file on behalf of the first useraccount, the one or more ACLs are modified for the shared folder and notfor the subfolder of the shared folder; and allow, by the cloud storagesystem, the external content handling application to access the file onbehalf of the first user account based on the user information of thefirst user account and the application information of the externalcontent handling application in the modified ACLs associated with theshared folder, wherein the modified ACLs associated with the sharedfolder prevent the external content handling application to access thefile on behalf of the second user account.
 16. The non-transitorycomputer-readable storage medium of claim 15, wherein the processingdevice is further to: receive another request to access the file fromthe external content handling application on behalf of the second useraccount; determine whether to grant or deny access to the file for theexternal content handling application on behalf of the second useraccount based on one or more user information and one or moreapplication information included in the modified ACLs associated withthe shared folder, the one or more user information including (i) theuser information of the first user account but not the user informationof the second user account and (ii) the one or more applicationinformation including the application information of the externalcontent handling application; and responsive to determining that theACLs associated with the shared folder include the applicationinformation of the external content handling application, but not theuser information of the second user account, deny access to the file forthe external content handling application on behalf of the second useraccount.
 17. The non-transitory computer-readable storage medium ofclaim 15, wherein to modify the one or more ACLs associated with theshared folder, the processing device is to: determine an ACL associatedwith the file as the one or more ACLs associated with the shared folder;modify the ACL associated with the file to include the user informationof the first user account and the application information of theexternal content handling application for granting the external contenthandling application access to the file on behalf of the first useraccount; determine another ACL associated with at least one of anotherfile of the shared folder, the subfolder of the shared folder, or one ormore files stored under the subfolder of the shared folder; and modifythe another ACL to correspond to the modified ACL associated with thefile.
 18. The non-transitory computer-readable storage medium of claim17, wherein the processing device is further to: receive a request ofthe external content handling application to access a file of the one ormore files stored under the subfolder of the shared folder on behalf ofthe first user account; determine that the another ACL is associatedwith the file of the one or more files stored under the subfolder of theshared folder; determine whether to grant or deny access to the file ofthe one or more files stored under the subfolder of the shared folder bythe external content handling application on behalf of the first useraccount based on one or more user information and one or moreapplication information included in the another ACL; and responsive todetermining that the another ACL includes the user information of thefirst user account and the application information of the externalcontent handling application, allow the external content handlingapplication to access the file of the one or more files stored under thesubfolder of the shared folder on behalf of the first user account. 19.The non-transitory computer-readable storage medium of claim 15, whereinthe external content handling application is executing on the userdevice to perform one or more operations with respect to file content,the one or more operations comprising at least one of presenting thefile content, modifying the file content, deleting at least a portion ofthe file content, adding new content to the file content, or playing thefile content.
 20. The non-transitory computer-readable storage medium ofclaim 15, wherein to receive the message granting access to the file,the processing device is further to verify that the first user accounthas privilege to grant access to the files.